THIS PAPER PRESENTS SOME OF THE Basis AND CONCEPTS OF SUBMARINE SHAPE DESIGN. USUALLY, THERE ARE SOME QUESTIONS ABOUT THE ORIGINS AND REASONS OF THE SELECTION OF OVERALL HYDRODYNAMIC SHAPE, THE DIAMETER AND LENGTH, THE BOW AND STERN SHAPE. THIS PAPER USES CFD METHOD FOR ANALYSIS OF SIX DIFFERENT MODEL OF SUBMARINE. THE RESISTANCE COEFFICIENTS OF EACH SHAPE ARE PRESENTED AND COMPARED SO THAT COULD UNDERSTAND THE REASON OF SUBMARINE SHAPE SELECTION WITH TAPERED STERN AND CURVED BOW. THE FOCUS OF THIS PAPER IS ON THE CYLINDRICAL MIDDLE BODY SUBMARINE SUCH AS THE MOST OF NAVAL SUBMARINES AND ROVS.DETERMINATION OF DIAMETER AND LENGTH OF SUBMARINE IS RELATED TO THE L/D RATIO THAT IS SOMEWHAT DISCUSSED HERE BY CFD MODELING.THE OUTLOOK OF THIS PAPER IS ON THE NAVAL SUBMARINES, AND SOME USEFUL NOTES ARE PRESENTED IN THIS FIELD.THE TOOLS OF CFD MODELING IS FLOW VISION (V.2.3) SOFTWARE THAT IS KNOWN AS A SKILLED SOFTWARE IN CFD MODELING.